This can be found the a book called, ‘Behold a Pale Horse’ by Milton William Cooper that was copyrighted in 1991.
Milton was a former U.S. Naval Intelligence Briefing Team Member, and felt it his duty to reveal information kept secret by our government since the 1940s. He was shot in the head by police. Some say he was assassinated, some say it was justified. You decide.

From Behold A Pale Horse PDF Page # 225

The government encouraged the manufacture and importation of
military firearms for the criminals to use. This is intended to foster a
feeling of insecurity, which would lead the American people to voluntarily
disarm themselves by passing laws against firearms. Using drugs and
hypnosis on mental patients in a process called Orion, the CIA inculcated
the desire in these people to open fire on schoolyards and thus inflame the
antigun lobby. This plan is well under way, and so far is working perfectly.
The middle class is begging the government to do away with the 2nd
Author’s Note: I have found that these events have indeed happened all over
the country. In every instance that I have investigated — the incident at the
women’s school in Canada, the shopping center incident in Canada, the Stockton,
California, massacre, and the murder of Rabbi Meir Kahane — the
shooters were all ex-mental patients or were current mental patients who were
ALL ON THE DRUG PROZAC! This drug, when taken in certain doses,
increases the serotonin level in the patient, causing extreme violence. Couple
that with a posthypnotic suggestion or control through an electronic brain
implant or microwave or E.L.F. intrusion and you get mass murder, ending in
every case with the suicide of the perpetrator. Exhume the bodies of the
murderers and check for a brain implant. I think you are going to be surprised.
In every case the name of the murderer’s doctor or mental treatment facility
has been withheld. I believe we will be able to establish intelligence-community
connections and/or connections to known CIA experimental mindcontrol
programs when we finally discover who these doctors of death really
Due to the wave of crime sweeping the nation, the media will convince
the American people that a state of anarchy exists within the major cities.
They are now building their case almost nightly on TV and daily in the
newspapers. When public opinion has been won to this idea, they intend
to state that a terrorist group armed with a nuclear weapon has entered the
United States and that they plan to detonate this device in one of our cities.
(This is now being set up by the crisis in the Middle East.) The Government
will then suspend the Constitution and declare martial law.

He wrote,

“I have brought you the truth as I know it … I have done my duty and no matter what fate lies in store for me, I can truly meet my maker with a clear conscience… THIS IS MY CREED – I believe first in God. The same God my ancestors believed in. I believe in Jesus Christ and that he is my Saviour. I believe second in the Constitution of the United States of America as it was written and meant to work. I have given my oath to protect and defend the Constitution against all enemies – foreign and DOMESTIC – and I intend to fulfil that oath. Third, I believe in the family unit and in particular, my family unit. I have sworn that I will give my life, if it is required, in defense of God, the Constitution, or my family. Fourth, I believe that any man without principals that he is ready and willing to die for at any given moment is already dead and of no use or consequence whatsoever.”
– William Cooper, August 3, 1990